James Bottomley <James.Bottomley@steeleye.com> writes:
> > How is the driver supposed to tell whether a given dma_addr_t value
> > represents consistent memory or not? It seems like an
> > (arch-specific) `dma_addr_is_consistent' function is necessary, but
> > I couldn't see one in your patch.
>
> If you have a machine that has both consistent and inconsistent blocks, you
> need to encode that in dma_addr_t (which is a platform definable type).
>
> The sync functions would just decode the type and either nop or perform the
> sync.
My thinking was that a driver might want to do things like --
if (dma_addr_is_consistent (some_funky_addr)) {
do it quickly;
} else
do_it_the_slow_way (some_funky_addr);
in other words, something besides just calling the sync functions, in
the case where the memory was consistent.
-Miles
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This archive was generated by hypermail 2b29 : Sat Dec 07 2002 - 22:00:21 EST